RE: [PATCH] xtensa: Increase size of gcc stack frame check

[David Laight]

From: Guenter Roeck
> Sent: 12 September 2021 03:53
> 
> xtensa frame size is larger than the frame size for almost all other
> architectures. This results in more than 50 "the frame size of <n> is
> larger than 1024 bytes" errors when trying to build xtensa:allmodconfig.
> 
> Increase frame size for xtensa to 1536 bytes to avoid compile errors
> due to frame size limits.

Have you done anything to check what happens at run-time?
I'd guess that the deepest stack use is inside printk() in
some obscure error path.

In reality all these 1k+ stack frames need killing
rather than the limit for the compiler warning increased.

While it may be sensible for a system call entry function
so allocate a reasonable size buffer on stack (as poll()
and sendmsg() probably do) allocating big buffers way
down the call stack could easily cause stack overflow.
Even a 1k stack frame is huge.

	David

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